Mainland police will have the authority to detain foreigners responsible for road accidents until their cases are closed, under new Ministry of Public Security regulations to come into effect in January.

Legal analysts said the new rules, announced on Wednesday, were in line with national legislation that prohibits foreigners involved in criminal or civil cases from leaving the country.

The new rules say motorists may be imprisoned for up to three years for causing traffic casualties, and those who flee from the scene of a fatal accident face a minimum seven years in jail.

Beijing lawyer Lu Wumao said the new regulations were in line with international practice and would not violate the personal freedoms of foreigners.

'The act is sensible and can better protect victims' interests,' Mr Lu said. 'It should have been introduced much earlier, but ... it takes time for a country's legislation system to mature.'

The new regulations also allow victims and their families to ask the court to freeze a defendant's assets ahead of any civil suits.

Foreigners can drive on the mainland if they obtain temporary licences, but few of them were in evidence until the recent development of more highways and better facilities.